Hepatocyte proteome destabilization and novel targets for PFASs unveiled through combined thermal proteome profiling

Zimeng Wu1, Yue Zou1, Kang Yang1

  • 1Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), Dalian Key Laboratory on Chemicals Risk Control and Pollution Prevention Technology, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.

PubMed

Insights

Identifying per- and polyfluoroalkyl substances (PFAS) protein targets is crucial for understanding toxicity. This study introduces an integrated thermal proteome profiling and deep transfer learning approach to efficiently discover novel PFAS-interacting proteins and their health implications.

Area of Science:

  • Environmental Chemistry
  • Toxicology
  • Proteomics

Background:

  • Per- and polyfluoroalkyl substances (PFAS) pose health risks, but their molecular targets remain largely unknown.
  • Reliable methods for identifying protein interactions with PFAS are limited.
  • Understanding PFAS-protein interactions is key to elucidating their toxicity mechanisms.

Purpose of the Study:

  • To develop and apply an integrated approach combining thermal proteome profiling (TPP) and deep transfer learning (DTL) for efficient identification of cellular PFAS targets.
  • To identify specific protein targets for representative PFAS compounds like PFOA, GenX, and Novec 649.
  • To investigate the potential health risks associated with identified PFAS-protein interactions, such as impacts on protein synthesis and cell apoptosis.

Main Methods:

  • Utilized thermal proteome profiling (TPP) coupled with nanospray liquid chromatography tandem mass spectrometry to measure PFAS binding proteins and affinities.
  • Developed deep transfer learning (DTL) models using neural network algorithms to predict PFAS-protein affinities.
  • Employed biolayer interferometry for experimental validation of specific PFAS-protein interactions.

Main Results:

  • PFAS uniquely destabilized the proteome of HepG2 cells, contrasting with stabilizing effects of other xenobiotics.
  • Identified key protein targets for PFOA, GenX, and Novec 649, showing weak binding affinities (median EC50 ≈ 30 μM).
  • The DTL model demonstrated high predictive accuracy (Pearson correlation coefficient = 0.89), outperforming previous models.
  • Discovered ribosomal proteins as novel targets for GenX, suggesting a link to apoptosis via disrupted protein synthesis.
  • Validated GenX binding to RPL4 protein, driven by electrostatic interactions and halogen bonds.

Conclusions:

  • The integrated TPP and DTL approach is effective for uncovering novel PFAS targets.
  • Identified protein targets provide new insights into the adverse health effects of PFAS exposure.
  • This methodology advances the understanding of PFAS toxicology and risk assessment.